The novel bi-level vacuum-actuated test fixture disclosed in United States utility patent application Ser. No. 586,010, invented by Golder et al and assigned to the same assignee as the instant invention, incorporated herein by reference, includes an electronic circuit device receiving face that is mounted for movement relative to a fixed probe support plate in such a way as to define a vacuum chamber therebetween. The probe support plate has mounted thereto a plurality of spring-loaded probes having ends that are constrained to lie on a first level defining an in-circuit testing array, and has mounted thereto a plurality of spring-loaded probes having ends that are constrained to lie on a second level different from the first level defining a functional testing array. A plurality of coil springs are mounted between and abutting the probe support plate and the electronic circuit board receiving face, and a plurality of spring-loaded buttons are mounted to the probe support plate. A bi-level vacuum source is operatively coupled to the vacuum chamber for selectively providing first and second preselected vacuum levels thereto. The first vacuum level is selected to have a magnitude greater than the combined resilient force provided by the plurality of coil springs but less than the resilient force of the coil springs and the spring-loaded buttons. The second preselected vacuum level is selected to have a magnitude greater than the combined resilient force of both the plurality of coil springs and of the spring-loaded buttons. Whenever the first, and lower, vacuum level is applied to the vacuum chamber, an electronic circuit device mounted to its receiving face is moved therewith into mechanical and electrical contact with the first plurality of spring-loaded probes as a result of a dynamic equilibrium condition established by the opposition between the vacuum pressure induced downward force and the upward conbined spring force of the springs and spring-loaded buttons. Whenever the full, and higher, vacuum level is applied to the vacuum chamber, the vacuum pressure induced force is sufficient to overcome the combined resilient force of the plurality of coil springs and spring-loaded buttons such that the electronic circut device moves into contact with the second plurality of spring-loaded probes.